Musicians practice and improve their skills by playing their instruments. Many of these instruments require hand and digit dexterity and strength. Musicians discovered many years ago that hand and digit exercises, in addition to playing their instruments, can improve their playing skills. They also learned that there are times when they cannot practice by playing their instruments because the sounds produced by the instruments disturb others "or because they are away from their instruments."
Piano and organ players attached weights to their fingers and wrists to improve strength and attain greater freedom of motion more than a century and a half ago. The benefits of such exercises were recognized at that time even though many people regularly exercised their finger, hand and arm muscles during normal daily chores such as milking cows and food preparation.
Finger fitness devices are known for the fretting hand of guitar players. These fitness devices include exercising with a spring resistance that is overcome by a finger. There are also guitar fitness fingerboards for guitarists. When exercising with these fingerboards, the guitarists depresses strings into contact with frets. The tension on the strings is adjustable. The height of each fret is also adjustable.
Finger fitness devices for pick the holding hand that are currently in use are general exercise devices designed for rehabilitation or for grip strength improvement. These devices are useful but do not address pick hand dexterity improvements for guitar players.